1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that: (1) source code distributions 7 * retain the above copyright notice and this paragraph in its entirety, (2) 8 * distributions including binary code include the above copyright notice and 9 * this paragraph in its entirety in the documentation or other materials 10 * provided with the distribution, and (3) all advertising materials mentioning 11 * features or use of this software display the following acknowledgement: 12 * ``This product includes software developed by the University of California, 13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 14 * the University nor the names of its contributors may be used to endorse 15 * or promote products derived from this software without specific prior 16 * written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 * 21 * $FreeBSD$ 22 */ 23 24 #define NETDISSECT_REWORKED 25 #ifdef HAVE_CONFIG_H 26 #include "config.h" 27 #endif 28 29 #include <tcpdump-stdinc.h> 30 31 #include <string.h> 32 33 #include "interface.h" 34 #include "addrtoname.h" 35 #include "ether.h" 36 #include "ethertype.h" 37 #include "extract.h" /* must come after interface.h */ 38 39 static const char tstr[] = "[|ARP]"; 40 41 /* 42 * Address Resolution Protocol. 43 * 44 * See RFC 826 for protocol description. ARP packets are variable 45 * in size; the arphdr structure defines the fixed-length portion. 46 * Protocol type values are the same as those for 10 Mb/s Ethernet. 47 * It is followed by the variable-sized fields ar_sha, arp_spa, 48 * arp_tha and arp_tpa in that order, according to the lengths 49 * specified. Field names used correspond to RFC 826. 50 */ 51 struct arp_pkthdr { 52 u_short ar_hrd; /* format of hardware address */ 53 #define ARPHRD_ETHER 1 /* ethernet hardware format */ 54 #define ARPHRD_IEEE802 6 /* token-ring hardware format */ 55 #define ARPHRD_ARCNET 7 /* arcnet hardware format */ 56 #define ARPHRD_FRELAY 15 /* frame relay hardware format */ 57 #define ARPHRD_ATM2225 19 /* ATM (RFC 2225) */ 58 #define ARPHRD_STRIP 23 /* Ricochet Starmode Radio hardware format */ 59 #define ARPHRD_IEEE1394 24 /* IEEE 1394 (FireWire) hardware format */ 60 u_short ar_pro; /* format of protocol address */ 61 u_char ar_hln; /* length of hardware address */ 62 u_char ar_pln; /* length of protocol address */ 63 u_short ar_op; /* one of: */ 64 #define ARPOP_REQUEST 1 /* request to resolve address */ 65 #define ARPOP_REPLY 2 /* response to previous request */ 66 #define ARPOP_REVREQUEST 3 /* request protocol address given hardware */ 67 #define ARPOP_REVREPLY 4 /* response giving protocol address */ 68 #define ARPOP_INVREQUEST 8 /* request to identify peer */ 69 #define ARPOP_INVREPLY 9 /* response identifying peer */ 70 #define ARPOP_NAK 10 /* NAK - only valif for ATM ARP */ 71 72 /* 73 * The remaining fields are variable in size, 74 * according to the sizes above. 75 */ 76 #ifdef COMMENT_ONLY 77 u_char ar_sha[]; /* sender hardware address */ 78 u_char ar_spa[]; /* sender protocol address */ 79 u_char ar_tha[]; /* target hardware address */ 80 u_char ar_tpa[]; /* target protocol address */ 81 #endif 82 #define ar_sha(ap) (((const u_char *)((ap)+1))+0) 83 #define ar_spa(ap) (((const u_char *)((ap)+1))+ (ap)->ar_hln) 84 #define ar_tha(ap) (((const u_char *)((ap)+1))+ (ap)->ar_hln+(ap)->ar_pln) 85 #define ar_tpa(ap) (((const u_char *)((ap)+1))+2*(ap)->ar_hln+(ap)->ar_pln) 86 }; 87 88 #define ARP_HDRLEN 8 89 90 #define HRD(ap) EXTRACT_16BITS(&(ap)->ar_hrd) 91 #define HRD_LEN(ap) ((ap)->ar_hln) 92 #define PROTO_LEN(ap) ((ap)->ar_pln) 93 #define OP(ap) EXTRACT_16BITS(&(ap)->ar_op) 94 #define PRO(ap) EXTRACT_16BITS(&(ap)->ar_pro) 95 #define SHA(ap) (ar_sha(ap)) 96 #define SPA(ap) (ar_spa(ap)) 97 #define THA(ap) (ar_tha(ap)) 98 #define TPA(ap) (ar_tpa(ap)) 99 100 101 static const struct tok arpop_values[] = { 102 { ARPOP_REQUEST, "Request" }, 103 { ARPOP_REPLY, "Reply" }, 104 { ARPOP_REVREQUEST, "Reverse Request" }, 105 { ARPOP_REVREPLY, "Reverse Reply" }, 106 { ARPOP_INVREQUEST, "Inverse Request" }, 107 { ARPOP_INVREPLY, "Inverse Reply" }, 108 { ARPOP_NAK, "NACK Reply" }, 109 { 0, NULL } 110 }; 111 112 static const struct tok arphrd_values[] = { 113 { ARPHRD_ETHER, "Ethernet" }, 114 { ARPHRD_IEEE802, "TokenRing" }, 115 { ARPHRD_ARCNET, "ArcNet" }, 116 { ARPHRD_FRELAY, "FrameRelay" }, 117 { ARPHRD_STRIP, "Strip" }, 118 { ARPHRD_IEEE1394, "IEEE 1394" }, 119 { ARPHRD_ATM2225, "ATM" }, 120 { 0, NULL } 121 }; 122 123 /* 124 * ATM Address Resolution Protocol. 125 * 126 * See RFC 2225 for protocol description. ATMARP packets are similar 127 * to ARP packets, except that there are no length fields for the 128 * protocol address - instead, there are type/length fields for 129 * the ATM number and subaddress - and the hardware addresses consist 130 * of an ATM number and an ATM subaddress. 131 */ 132 struct atmarp_pkthdr { 133 u_short aar_hrd; /* format of hardware address */ 134 u_short aar_pro; /* format of protocol address */ 135 u_char aar_shtl; /* length of source ATM number */ 136 u_char aar_sstl; /* length of source ATM subaddress */ 137 #define ATMARP_IS_E164 0x40 /* bit in type/length for E.164 format */ 138 #define ATMARP_LEN_MASK 0x3F /* length of {sub}address in type/length */ 139 u_short aar_op; /* same as regular ARP */ 140 u_char aar_spln; /* length of source protocol address */ 141 u_char aar_thtl; /* length of target ATM number */ 142 u_char aar_tstl; /* length of target ATM subaddress */ 143 u_char aar_tpln; /* length of target protocol address */ 144 /* 145 * The remaining fields are variable in size, 146 * according to the sizes above. 147 */ 148 #ifdef COMMENT_ONLY 149 u_char aar_sha[]; /* source ATM number */ 150 u_char aar_ssa[]; /* source ATM subaddress */ 151 u_char aar_spa[]; /* sender protocol address */ 152 u_char aar_tha[]; /* target ATM number */ 153 u_char aar_tsa[]; /* target ATM subaddress */ 154 u_char aar_tpa[]; /* target protocol address */ 155 #endif 156 157 #define ATMHRD(ap) EXTRACT_16BITS(&(ap)->aar_hrd) 158 #define ATMSHRD_LEN(ap) ((ap)->aar_shtl & ATMARP_LEN_MASK) 159 #define ATMSSLN(ap) ((ap)->aar_sstl & ATMARP_LEN_MASK) 160 #define ATMSPROTO_LEN(ap) ((ap)->aar_spln) 161 #define ATMOP(ap) EXTRACT_16BITS(&(ap)->aar_op) 162 #define ATMPRO(ap) EXTRACT_16BITS(&(ap)->aar_pro) 163 #define ATMTHRD_LEN(ap) ((ap)->aar_thtl & ATMARP_LEN_MASK) 164 #define ATMTSLN(ap) ((ap)->aar_tstl & ATMARP_LEN_MASK) 165 #define ATMTPROTO_LEN(ap) ((ap)->aar_tpln) 166 #define aar_sha(ap) ((const u_char *)((ap)+1)) 167 #define aar_ssa(ap) (aar_sha(ap) + ATMSHRD_LEN(ap)) 168 #define aar_spa(ap) (aar_ssa(ap) + ATMSSLN(ap)) 169 #define aar_tha(ap) (aar_spa(ap) + ATMSPROTO_LEN(ap)) 170 #define aar_tsa(ap) (aar_tha(ap) + ATMTHRD_LEN(ap)) 171 #define aar_tpa(ap) (aar_tsa(ap) + ATMTSLN(ap)) 172 }; 173 174 #define ATMSHA(ap) (aar_sha(ap)) 175 #define ATMSSA(ap) (aar_ssa(ap)) 176 #define ATMSPA(ap) (aar_spa(ap)) 177 #define ATMTHA(ap) (aar_tha(ap)) 178 #define ATMTSA(ap) (aar_tsa(ap)) 179 #define ATMTPA(ap) (aar_tpa(ap)) 180 181 static u_char ezero[6]; 182 183 static void 184 atmarp_addr_print(netdissect_options *ndo, 185 const u_char *ha, u_int ha_len, const u_char *srca, 186 u_int srca_len) 187 { 188 if (ha_len == 0) 189 ND_PRINT((ndo, "<No address>")); 190 else { 191 ND_PRINT((ndo, "%s", linkaddr_string(ndo, ha, LINKADDR_ATM, ha_len))); 192 if (srca_len != 0) 193 ND_PRINT((ndo, ",%s", 194 linkaddr_string(ndo, srca, LINKADDR_ATM, srca_len))); 195 } 196 } 197 198 static void 199 atmarp_print(netdissect_options *ndo, 200 const u_char *bp, u_int length, u_int caplen) 201 { 202 const struct atmarp_pkthdr *ap; 203 u_short pro, hrd, op; 204 205 ap = (const struct atmarp_pkthdr *)bp; 206 ND_TCHECK(*ap); 207 208 hrd = ATMHRD(ap); 209 pro = ATMPRO(ap); 210 op = ATMOP(ap); 211 212 if (!ND_TTEST2(*aar_tpa(ap), ATMTPROTO_LEN(ap))) { 213 ND_PRINT((ndo, "%s", tstr)); 214 ND_DEFAULTPRINT((const u_char *)ap, length); 215 return; 216 } 217 218 if (!ndo->ndo_eflag) { 219 ND_PRINT((ndo, "ARP, ")); 220 } 221 222 if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) || 223 ATMSPROTO_LEN(ap) != 4 || 224 ATMTPROTO_LEN(ap) != 4 || 225 ndo->ndo_vflag) { 226 ND_PRINT((ndo, "%s, %s (len %u/%u)", 227 tok2str(arphrd_values, "Unknown Hardware (%u)", hrd), 228 tok2str(ethertype_values, "Unknown Protocol (0x%04x)", pro), 229 ATMSPROTO_LEN(ap), 230 ATMTPROTO_LEN(ap))); 231 232 /* don't know know about the address formats */ 233 if (!ndo->ndo_vflag) { 234 goto out; 235 } 236 } 237 238 /* print operation */ 239 ND_PRINT((ndo, "%s%s ", 240 ndo->ndo_vflag ? ", " : "", 241 tok2str(arpop_values, "Unknown (%u)", op))); 242 243 switch (op) { 244 245 case ARPOP_REQUEST: 246 ND_PRINT((ndo, "who-has %s", ipaddr_string(ndo, ATMTPA(ap)))); 247 if (ATMTHRD_LEN(ap) != 0) { 248 ND_PRINT((ndo, " (")); 249 atmarp_addr_print(ndo, ATMTHA(ap), ATMTHRD_LEN(ap), 250 ATMTSA(ap), ATMTSLN(ap)); 251 ND_PRINT((ndo, ")")); 252 } 253 ND_PRINT((ndo, "tell %s", ipaddr_string(ndo, ATMSPA(ap)))); 254 break; 255 256 case ARPOP_REPLY: 257 ND_PRINT((ndo, "%s is-at ", ipaddr_string(ndo, ATMSPA(ap)))); 258 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), 259 ATMSSLN(ap)); 260 break; 261 262 case ARPOP_INVREQUEST: 263 ND_PRINT((ndo, "who-is ")); 264 atmarp_addr_print(ndo, ATMTHA(ap), ATMTHRD_LEN(ap), ATMTSA(ap), 265 ATMTSLN(ap)); 266 ND_PRINT((ndo, " tell ")); 267 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), 268 ATMSSLN(ap)); 269 break; 270 271 case ARPOP_INVREPLY: 272 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), 273 ATMSSLN(ap)); 274 ND_PRINT((ndo, "at %s", ipaddr_string(ndo, ATMSPA(ap)))); 275 break; 276 277 case ARPOP_NAK: 278 ND_PRINT((ndo, "for %s", ipaddr_string(ndo, ATMSPA(ap)))); 279 break; 280 281 default: 282 ND_DEFAULTPRINT((const u_char *)ap, caplen); 283 return; 284 } 285 286 out: 287 ND_PRINT((ndo, ", length %u", length)); 288 return; 289 290 trunc: 291 ND_PRINT((ndo, "%s", tstr)); 292 } 293 294 void 295 arp_print(netdissect_options *ndo, 296 const u_char *bp, u_int length, u_int caplen) 297 { 298 const struct arp_pkthdr *ap; 299 u_short pro, hrd, op, linkaddr; 300 301 ap = (const struct arp_pkthdr *)bp; 302 ND_TCHECK(*ap); 303 304 hrd = HRD(ap); 305 pro = PRO(ap); 306 op = OP(ap); 307 308 309 /* if its ATM then call the ATM ARP printer 310 for Frame-relay ARP most of the fields 311 are similar to Ethernet so overload the Ethernet Printer 312 and set the linkaddr type for linkaddr_string(ndo, ) accordingly */ 313 314 switch(hrd) { 315 case ARPHRD_ATM2225: 316 atmarp_print(ndo, bp, length, caplen); 317 return; 318 case ARPHRD_FRELAY: 319 linkaddr = LINKADDR_FRELAY; 320 break; 321 default: 322 linkaddr = LINKADDR_ETHER; 323 break; 324 } 325 326 if (!ND_TTEST2(*ar_tpa(ap), PROTO_LEN(ap))) { 327 ND_PRINT((ndo, "%s", tstr)); 328 ND_DEFAULTPRINT((const u_char *)ap, length); 329 return; 330 } 331 332 if (!ndo->ndo_eflag) { 333 ND_PRINT((ndo, "ARP, ")); 334 } 335 336 /* print hardware type/len and proto type/len */ 337 if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) || 338 PROTO_LEN(ap) != 4 || 339 HRD_LEN(ap) == 0 || 340 ndo->ndo_vflag) { 341 ND_PRINT((ndo, "%s (len %u), %s (len %u)", 342 tok2str(arphrd_values, "Unknown Hardware (%u)", hrd), 343 HRD_LEN(ap), 344 tok2str(ethertype_values, "Unknown Protocol (0x%04x)", pro), 345 PROTO_LEN(ap))); 346 347 /* don't know know about the address formats */ 348 if (!ndo->ndo_vflag) { 349 goto out; 350 } 351 } 352 353 /* print operation */ 354 ND_PRINT((ndo, "%s%s ", 355 ndo->ndo_vflag ? ", " : "", 356 tok2str(arpop_values, "Unknown (%u)", op))); 357 358 switch (op) { 359 360 case ARPOP_REQUEST: 361 ND_PRINT((ndo, "who-has %s", ipaddr_string(ndo, TPA(ap)))); 362 if (memcmp((const char *)ezero, (const char *)THA(ap), HRD_LEN(ap)) != 0) 363 ND_PRINT((ndo, " (%s)", 364 linkaddr_string(ndo, THA(ap), linkaddr, HRD_LEN(ap)))); 365 ND_PRINT((ndo, " tell %s", ipaddr_string(ndo, SPA(ap)))); 366 break; 367 368 case ARPOP_REPLY: 369 ND_PRINT((ndo, "%s is-at %s", 370 ipaddr_string(ndo, SPA(ap)), 371 linkaddr_string(ndo, SHA(ap), linkaddr, HRD_LEN(ap)))); 372 break; 373 374 case ARPOP_REVREQUEST: 375 ND_PRINT((ndo, "who-is %s tell %s", 376 linkaddr_string(ndo, THA(ap), linkaddr, HRD_LEN(ap)), 377 linkaddr_string(ndo, SHA(ap), linkaddr, HRD_LEN(ap)))); 378 break; 379 380 case ARPOP_REVREPLY: 381 ND_PRINT((ndo, "%s at %s", 382 linkaddr_string(ndo, THA(ap), linkaddr, HRD_LEN(ap)), 383 ipaddr_string(ndo, TPA(ap)))); 384 break; 385 386 case ARPOP_INVREQUEST: 387 ND_PRINT((ndo, "who-is %s tell %s", 388 linkaddr_string(ndo, THA(ap), linkaddr, HRD_LEN(ap)), 389 linkaddr_string(ndo, SHA(ap), linkaddr, HRD_LEN(ap)))); 390 break; 391 392 case ARPOP_INVREPLY: 393 ND_PRINT((ndo,"%s at %s", 394 linkaddr_string(ndo, SHA(ap), linkaddr, HRD_LEN(ap)), 395 ipaddr_string(ndo, SPA(ap)))); 396 break; 397 398 default: 399 ND_DEFAULTPRINT((const u_char *)ap, caplen); 400 return; 401 } 402 403 out: 404 ND_PRINT((ndo, ", length %u", length)); 405 406 return; 407 trunc: 408 ND_PRINT((ndo, "%s", tstr)); 409 } 410 411 /* 412 * Local Variables: 413 * c-style: bsd 414 * End: 415 */ 416 417